Telecommunications networks have traditionally provided subscriber services by connecting them to the nearest telephone office with copper wires. Each subscriber was allocated the number of wires necessary for the type of service. The assignment of wires was dedicated to each subscriber. For example, a plain old telephone service (POTS) subscriber typically required one pair of copper wires for each telephone number.
As technology advanced, it was possible to digitally multiplex and concentrate more subscribers on a less number of copper wires. A typical example is the Digital Loop Carrier (DLC) as described in a Bellcore document TR-TSY-OOO8. In DLC, the telecommunications network provide service to subscribers through the support of remote subscriber terminals connected to central office terminals. The DLC technology allows a single remote terminal to be connected to a single central terminal. These remote subscriber terminals connect directly to the subscribers premise providing such services as POTS, coin, ISDN, and Wideband. The central office terminals provide connections to the local exchange switch and thus the rest of the telecommunications network. In DLC, a fixed traffic concentration not exceeding 2:1 was possible between the single central office terminal and single remote terminal.
Further technical advances have allowed multiple remote terminals to be connected to a single central terminal as in Optical Line Terminal to Optical Network Unit (OLT-ONU) configurations where a single OLT supports multiple ONUs). This is typically configured in a cascaded or dual cascaded configuration emanating from the central office terminal. For both the DLC and OLT-ONU configurations, a standard line interface is used to connect the remote terminals to their central office terminal. The control of the central office terminal and the remote terminal(s) connection is also not transparent to the network facility connecting them. Further, these configurations are disadvantageously limited to the size of the terminals and the capacity of the line connecting the terminals.